# [−][src]Function mynewt::kernel::os::os_callout_init

    pub unsafe extern "C" fn os_callout_init(
        cf: *mut os_callout,
        evq: *mut os_eventq,
        ev_cb: os_event_fn,
        ev_arg: *mut c_void
    )

Initialize a callout.

Callouts are used to schedule events in the future onto a task's event queue. Callout timers are scheduled using the os_callout_reset() function. When the timer expires, an event is posted to the event queue specified in os_callout_init(). The event argument given here is posted in the ev_arg field of that event.

- `c`: The callout to initialize
- `evq`: The event queue to post an OS_EVENT_T_TIMER event to
- `timo_func`: The function to call on this callout for the host task used to provide multiple timer events to a task (this can be NULL.)
- `ev_arg`: The argument to provide to the event when posting the timer.

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